This is the most common malignant tumour in the West and is the third most common cause of death in the UK after heart disease and pneumonia.
In the UK, 32 000 people die each year from bronchial carcinoma, with a male-to-female ratio of 3: 1.
Non-small-cell carcinoma
1-Squamous cell carcinoma
Is the commonest type, accounting for approximately 40% of all carcinomas
Most present as obstructive lesions of the bronchus leading to infection.
It occasionally cavitates (10%) at presentation.
Local spread is common but widespread metastases occur relatively late
Produce ectopic hormones:
- Ectopic PTH
- Ectopic TSH
- Other features include: HPOA, Gynaecomastia and clubbing
2-Adenocarcinoma
Adenocarcinoma accounts for approximately 10% of all carcinomas
Arises from mucous cells in the bronchial epithelium
Invasion of the pleura and the mediastinal lymph nodes is common
Metastases to the brain and bones.
Associated with asbestos and is proportionally more common in non-smokers
3-Large cell carcinomas
These account for about 25% of all lung cancers
Metastasize early
4-Bronchoalveolar cell carcinoma
Accounts for only 1-2% of lung tumours
Occurs either as a peripheral solitary nodule or as diffuse nodular lesions of multicentric origin
Occasionally this tumour is associated with expectoration of very large volumes of mucoid sputum
Small-cell carcinoma
Accounts for 20-30% of all lung cancers.
It arises from endocrine cells (Kulchitsky cells), These cells are members of the APUD system, which explains why many polypeptide hormones are secreted by these tumours.
It produces:
- SIADH
- Ectopic ACTH
- Eton-Lambert syndrome
Small-cell carcinoma spreads early and is almost always inoperable at presentation
It is radiotherapy resistant but responds to chemotherapy however the prognosis remains poor.
Poor prognostic features:Na>132,wt loss>10%,performance state >2,ALP>1.5 of normal,LDH>1.5 of normal and extensive disease.
Diagnosis
- Bronchoscopy and biopsy/bronchial brushing (80% within the reach of the scope)
- Sputum cytology
- Per cutaneous needle biopsy
- CT san of chest (and head & liver for staging)
Treatment
Surgical:
85% not respectable
Contraindication to surgery:
Metastasis
Mediastinal organ invasion
Malignant pleural effusion
Contralateral mediastinal node
FEV1 <0.8 L
Severe cardiac /other conditions
Radiotherapy:
Radical especially in conjunction with chemotherapy
Palliative for SVCO
Combined chemotherapy:
Useful in small cell cancer